Question: William ate 2 slices of cake. Umaima ate 4 slices. If William ate $\dfrac{2}{7}$ of the cake, what fraction of the cake was eaten?
If 2 slices represent $\dfrac{2}{7}$ of the cake, there must have been a total of 7 slices. $\text{fraction of cake eaten} = \dfrac{\text{number of slices eaten}}{\text{number of slices total}}$ They ate ${6}$ out of $7$ slices. They ate $\dfrac{6}{7}$ of the cake.